California’s new hands-free cell phone law could save 300 lives a year, a new study indicates.

Similar laws in other states already have saved lives, the Public Policy Institute of California reported Monday night. In particular, those laws have helped reduce the number of deaths from accidents that occurred in bad weather, on wet roads or during rush-hour. “The hands-free law has the potential to change people’s behavior in lots of ways,” said Jed Kelko, a research fellow at the PPIC, an independent, non-profit, nonpartisan research group. But Kelko, who wrote the report, noted the benefit of such laws “is really concentrated in adverse driving conditions.” His findings appear to sharply contradict data from the California Highway Patrol. According to the CHP, cell phone usage was a factor in just six fatal accidents in 2006, the last year for which data was available.

Taking effect on July 1, California’s law will require drivers to use a hands-free device such as a Bluetooth headset when talking on their cell phones while behind the wheel. A separate law bars those younger than 18 from using a cell phone or other mobile device at all while driving.

The hands-free law is aimed at reducing what many see as a growing danger: drivers distracted by the cell phones pressed against their ears.

“I believe this (law) will save lives,” said State Sen. Joe Simitian, D-Palo Alto, who was the chief sponsor of the law. Noting the PPIC’s new study, he added, “The latest data suggests that’s absolutely the case.” To assess the potential impact of California’s new law, Kolko took a look at crash data from other states that have already implemented similar rules and compared it to data from states without such laws. New York, New Jersey, Connecticut and the District of Columbia enacted hands-free laws before California.

Kolko then compared other potential factors, including the fact that traffic deaths have been trending downward nationwide. He found that in the first six months after the hands-free laws took effect, traffic deaths in bad weather for states with those laws were 52 percent lower than they would have been expected to be. Wet road fatalities were 38 percent lower, and rush-hour deaths were 17 percent lower.

The effect was inconsistent over time. But data from New York, which in 2001 enacted the first hands-free law, suggest that it holds up over the long term. Three to four years into New York’s law, bad weather traffic deaths were 63 percent lower than would be expected, while wet road deaths were 64 percent lower than expected.

Assuming that California would see similar percentage declines in death rates, Kelko applied those figures to the state’s total number of annual fatalities in adverse conditions. That’s how he got the 300 figure, which he calls a “conservative estimate.” Kelko’s research doesn’t explain why hands-free laws lower traffic related deaths. There’s not enough data yet to know, he said.

Conservative though Kelko’s numbers may be, his research may still prove controversial, in light of CHP’s data. Between 2004 and 2006, CHP reported no more than 8 fatal accidents a year involving cell phone usage.

That number is not directly comparable with the PPIC’s, because more than one person could have died in each of those crashes. However it does suggest that far fewer people are dying on California roads due to talking on a cell phone than the PPICs reports the new law will save.

Cell phone usage prior to a collision is likely significantly underreported, Kelko argues, because of the difficulty in assessing it after the fact.

Conversely, other studies have suggested that talking on a hands-free device is much more dangerous than either the CHP figures indicate or the PPIC study suggests. Those studies contend that talking on a cell phone while driving is just as dangerous as driving while legally drunk _ regardless of whether the driver is using a hands-free device or not.

“The problem isn’t that drivers’ hands aren’t on the wheel,” said David Meyer, a professor of psychology at the University of Michigan. “It’s that their mind is not on the road.” Kolko doesn’t dispute the notion that cell phone usage — hands-free or no — can impair driving. But his research indicates that hands-free laws may help in other ways, such as by alerting drivers to the dangers of driving while on a cell phone or encouraging them to use cell phones only when conditions might permit them to be used more safely, he said.

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